JP-A-8-255981 discloses a technology in which, by using an exposing process for a photo sensitive material with ultraviolet light, microscopic via holes and wirings are formed on a glass substrate. In the document, through forming a light shielding film of a metal constituting of such as Ti, Cr, Al, Ni, W, Mo, Ta and Cu on the glass substrate, multiple reflection of ultraviolet between the upper and lower faces of the glass substrate is prevented at the time of the exposing process of the photo sensitive material. Further, through forming the film thickness of the light shielding film constituted by one of the above metals more than 3 μm, the heat conductivity of the glass substrate is enhanced.
JP-A-9-321184 discloses a connection substrate for connecting a semiconductor chip having a high wiring density with a printed wire substrate having a low wiring density and manufacturing method thereof. The connection substrate is constituted by a photosensitive glass substrate and on the upper face thereof one layer wiring is formed to which a bump for the chip is connected. Further, on the lower face of the substrate a plurality of bumps are formed, which are connected to electrodes on the printed wire substrate. The wirings on the upper face of the substrate and the bump on the lower face are electrically connected through holes penetrating between the upper and lower faces of the substrate. These penetrating holes are formed through a photolithography and the insides thereof conductors are buried through plating.
JP-A-2000-124358 discloses a technology of a high frequency integrated circuit mounting an active element in which an MIM type capacitor, a spiral inductor, a thin film resistor and metal wirings for connecting these are arranged on a silicon substrate and further, a flip chip is mounted thereon. Further, the claims thereof cover the use of a glass substrate, although the details thereof and the advantages thereof are not disclosed.
JP-A-10-284694 discloses a technology of constituting an electronic circuit on a poly crystal silicon substrate having a resistivity of more than 200 Ωcm.
As the wiring substrate for mounting an electronic parts, one in which Cu wirings are formed on a resin substrate constituted such as epoxy resin containing glass fibers (glass epoxy) and polyimide resin or one in which W wirings are formed on a ceramics substrate such as AlN and SiC are broadly used.
However the warp and size variation of the wiring materials such as the resin and the ceramics are large in comparison with those of silicon substrate which is used in the manufacture of the semiconductor integrated circuits and the formation of microscopic wirings and through holes of the order of μm by using a photolithography is impossible, therefore, it was difficult to mount the electronic parts in high density.
On the other hand, as the wiring substrate for mounting electronics parts, the general use property of the silicon substrate, which is suitable for forming the microscopic wirings is low in comparison with such as the glass epoxy substrate, and it's usage is limited. Further, since the single crystal silicon substrate is a semiconductor, the substrate operates to reduce the efficiency of the electronic parts such as a capacitor and inductor formed thereon. On the other hand, the poly crystal silicon substrate can prevent in some extent the efficiency reduction, however, the poly crystal silicon substrate is more expensive than the single crystal silicon and the general use property thereof as the wiring substrate for mounting electronic parts is low and the usage thereof is limited.
Since the glass shows characteristics that the warp and the size variation are small in comparison with such as the resin and ceramics and the cost thereof is inexpensive in comparison with the silicon, it is considered that glass is a suitable substrate material for mounting electronic parts in high density. Further, the glass substrate is a desirable insulator, therefore the elements such as the inductors formed thereon show a high efficiency.
However, since the heat conductivity of the ordinal glass substrate as disclosed on JP-A-2000-124358 is low and is likely broken, such as cracks and damages are frequently caused due to difference of the thermal expansion coefficients between the glass substrate and other materials (Si), as a result, yield thereof reduces and the reliability thereof also reduces.
Further, in order to mount electronic parts on the glass substrate in high density as well as to use the glass substrate in a broad usage, it is necessary to lead out electrodes to be used as external connection terminals from the back face of the substrate (opposite side face from the mounting face of the electronic parts) as being practiced in the wiring substrate of such as resin and ceramics.
In order to lead out the external connection terminals from the back face of the substrate, it is necessary to form through holes in the glass substrate in high accuracy, however, if a special photosensitive glass as, for example, disclosed in JP-A-9-321184 is used, the manufacturing cost of the substrate increases and it's usage is limited as the substrate for mounting the electronic parts.
Further, as disclosed in JP-A-2000-124358 when all of the variety of the electronic parts such as the capacitor, inductor and resistor are arranged on the substrate, the size of the integrated electronic parts become comparatively large.
Further, in the above document, since the respective constituting elements formed on the glass substrate are structured to be exposed at the end face of the substrate, when a large mechanical stress is applied at the interface regions of the respective layers constituting the electronic circuit component at the time of cutting out such as by dicing from the glass substrate larger than the electronic part, and when a large thermal stress is applied at the interfaces of the respective layers in connection with sudden temperature variation caused at the time of mounting the electronic circuit component, these stresses are concentratedly applied on the substrate exposed at the end faces of the electronic circuit component and the interface regions of the respective layers, thereby, the interface regions of the respective layers may be peeled off and the electronic circuit component may be damaged.
Accordingly, these already known electronic circuit components do not necessarily show a high reliability, in addition, it was not necessarily easy to obtain a high manufacturing yield.
An object of the present invention is to provide an electronic circuit component, which integrates a variety of electronic parts such as a capacitor, inductor and resistor in a high performance and in a high density.